Railway-traffic-controlling apparatus



April 22, 1930. R. A. M CANN RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed March 27,

1924 2 Sheets-Sheet l IINVENTOR'. m. 744/ CQVM,

A144; ATTORNEY April 22, 1930. I MCCANN 1,755,357

RAILWAY TRAFFIC CONTROLLING APPARATUS Original. Filed March 2'7; 1924 2 Sheets-Sheet 2 INVENTOR T Patented Apr. 1930 FIcE RONALD A. MoCANN, OF SWISSVALE, PENNSYLVANIA, ASSIGNDR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE,

PENNSYLVANIA PENNSYLVANIA, A CORPORATION OF RAILWAY-TRAFFIG-CONTROLLING APPARATUS Continuation of application Serial No. 702,286, filed March 27, 1924. This application filed October 4,

1924. Serial My invention relates to railway traffic controlling apparatus, and particularly to apparatus of the type comprising governing mechanism located on a train and controlled from the trackway.

In apparatus of this character it has been customary to provide a low speed limit under unsafe traffic conditions, whereby after entering the unsafe zone the train may proceed without an automatic brake application, provided its speed does not exceed such limit. As a further element of safety it has been suggested that while proceeding through the unsafe zone the engineer should be required to perform a manual acknowledging act at periodic intervals in order to give evidence of the fact that he is cognizant of the condition under which he is traveling, the penalty for failure to perform such act at the proper intervals being an automatic brake'application, even if the speed of the train is below the given low value.

One feature of my invention is the provision of a novel and improved means for requiring such acknowledgment on the part of the engineer.

The present application is a continuation of my co-pending application, Serial No. 702,286, filed March 27, 1924, v for railway trailic controlling apparatus.

I will describe two forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic view showing one form of apparatus embodying my invention. Fig. 2 is a top plan view of the timing device T of Fig. 1. Fig. 3 isa view showing amodification of a portion of the train carried apparatus of Fig. 1 and also embodying my invention. Fig. t is a view showing another modification of the train carried apparatus shown in Fig. 1 and also embodying my invention.

Referring first to Fig. 1, the reference characters 15 and '15 designate the track rails of railway along which traffic normally moves in the direction indicated by the arrow. These rails are divided by insulated joints 16 into a plurality of track sections, of which only one complete section A.B is shown in the drawing.

Each track section is provided with a track circuit comprising a source of current connected across the rails at one end of the section and a track relay connected across the rails at the other end of the section. In the form here shown, the source of track circuit current is a battery D, and the track relay is of the direct current type designated by the reference character K with an exponent corresponding to the location.

Each section is also provided with a track way signal designated by the reference char acter S with an exponent corresponding to the location, each of which signals is controlled by the track relays in the usual manner, so that the signal indicates proceed, caution, or stop, according to traflic conditions in advance of the signal. The control of these signals by the track relays forms no part of my present invention, and so the controlling circuits are omitted from the drawing to simplify the disclosure.

Means are provided for supplying an alternating train governing current to the rails of each track section, which current is furnished by a generator G connected with a transmission line H. This train governing current is'applied to the track rails by a transformer designated by the reference character E with an exponent corresponding to the location, the secondary of which transformer is connected in the track circuit between one terminal of the track battery I) and one of the track rails. The primary circuit for each transformer is controlled by a front contact 20 of thetrack relay K for the section next in advance, such primary circuit including the secondary of a line transformer F the primary of which is connected across the transmission line H. It will be seen, therefore, that alternating train governing current is applied to the track rails of each section except the section in the rear of an occupied section.

Located in the section immediately to the left of point A is a train L, which is provided'with a circuit a adapted to receive alter-. nating energy inductively from the track rails 15 and 15: In the form here shown this circuit includes two pick-up coils 18, 18 wound respectively on two magnetizable cores 17, 17 a which are disposed above, and transversely with relation to, the two rails 15 and 15 The energy thus induced in the receiving circuit a is employed to control a train carried relay R in such manner that this relay is energized when the train occupies a section of track which is supplied with alternating train governing current, but is de-energized when the train occupies a section of track which is not supplied with such current. Preferably an amplifier 19 is interposed between the receiving circuit a and the main relay R. r

The train L is also provided with a magnet M controlling a valve V in a brake governing pipe 2 in such manner that de-energization of the magnet M causes an automatic application of the brakes. When the relay R is energized, magnet M is energized by a circuit which passes from terminal Bof a suitable source of current through contact 4 of relay R, wires 5 and 6, win ling of magnet I M, and wire 7 to terminal 0 of the same source of current. When relay R is energized, therefore, the train is free to proceed at any speed without incurring an automatic application of the brakes, although if desired means may be interposed in the circuit just traced for magnet M whereby this magnet will be deenergized if the train exceeds a given high speed even though relay R is energized.

Also located on the train is a centrifugal device C operated by a wheel 3 which in turn is connected by gearing with a wheel of the train. This centrifugal device C controls a contact 13 in such manner that the contact is open at speeds above a safe low value, such as 15 miles per hour, and is closed if the speed does not exceed such value.

The train is also provided with a slow acting device T comprising a normally open contact 11 -11 and a normally closed contact 1010". Considering also Fig. 2, device T comprises a slow releasing mechanism 26 having a spindle 27 adapted to wind up the mechanism when the spindle is rotated in clockwise direction as viewed in Fig. 1. When the spindle is subsequently released the spindle rotates with a uniform slow angular velocity in a counter clockwise direction as viewed in Fig. 1, and after an interval of time returns to its original position. ()ne form of slow releasing mechanism which may be employed is disclosed in United States Letters Patent No. 992,236, granted to vV. P. Neubert and V. H. McClelland on the 16th day of May, 1911. In that patent shaft 11 corresponds to spindle 27 of the present disclosure.

Rigidly secured to spindle 27 is a substantially circular cam 28 having a radially projecting cam surface 28 for operating con-- tact 11 11 A knob 32 is loosely mounted on spindle 27 and is provided, on its rear face, with a backwardly projecting stud 30 which enters an arcuate slot 29 in cam 28. -Knob 32 is further provided with afinger 31 for operating contact 10 1O By means of a spring e0 attached to finger 31, knob 32 is biased to the position shown in the drawing, in which position contact '10 --10 is closed by finger 31, and further counter clockwise rotation of knob 32 is prevented by the engagement of finger 31 with contact member 10. The mechanism 26 is so arranged that cam 28 is constantly urged to rotate in a counter clockwise'direction'but this camis normally restrained from'such rotation, as will be clear from the drawing, by the engagement of stud 30 with the end of slot 29.

As shown in the drawing then, the device is in its run down condition and contact 10**1O is closed by finger 31, but surface 28 of cam 28 does not engage contact member 11 and so contact 11-11 is open.

To operate the timing device, the engineer grasps knob 32 and turns it in a clockwise direction till finger 31 engages a fixed stop 31. This movement of knob 32 opens contact 10-10", and also causes stud 30 to move cam 28 to such position that cam surface 28 closes contact 11 -11 When the engineer releases knob 32, spring 40 immediately returns the knob to the position shown in the drawing, thus again closing contact 1010. Cam 28 returns more slowly, being retarded by the slow releasing mechanism 26. During this return motion of cam 28, stud 30 is free in slot 29. After an interval of time cam 28 returns to the position shown in the drawing, whereupon contact 11-11 again opens.

The brake controlling magnet 1W1 is provided with an auxiliary circuit which passes from terminal B of the said source of current, through back contact 8 of relay R, wire 9, contact 1010 wire 25, contact 11-11", wire 12, contact 13, wires 14. and 6, magnet M, and wire 7 to terminal 0 of the same source of current. lt will be seen that this auxiliary circuit is closed when relay R is de-energized, provided that contacts 10=-i0 and 11-11 are both closed and the speed of the train does not exceed the safe low value.

As shown in the drawing, the track section immediatelyto the right of point B is occupied by a second train L so that signal S indicates stop and signal S indicates caution. The circuit a on the first train L is receiving train governing current from the track rails so that relay R is energized, with the result that the brake controlling magnet M is also energized through its main circuit controlled by front contact t of relay R. When the train L enters section A-L, the supply of train governing current to its receiving circuit a will be discontinued because contact 20 of track relay H is open, and so the main relay R on train L will become'de-energized. If the speed of the train does not exceed 15 miles per hour and the engineer operates the circuit controller T to close the contact 11 l1 the auxiliary circuit for brake magnet M will be closed, and so the train can proceed Without an automatic application of the brakes. The parts are so arranged that the time required to apply the brakes after de-energization of magnet M is slightly greater than the time interval during which contact 1O"*1O is open during operation of device T. If the speed of the train at any instant exceeds 15 miles per hour, contact 18 will open, so that the brakes Will be applied and the train will be brought to a stop. Furthermore, if the engineer does not operate the device T prior to the expiration of the time element of this device, contact 1111 will open, and so the brakes will be applied and the train will be brought to a stop. The time element of device T may be any suitable value, such for example as the average time r quired for the train to traverse an entire track section at 15 miles per hour,

I in which instance manual operation of the device T by the engineer will be required just prior to passing each signal S as long as the two trains continue to run in adjoining sections. It is understood, however, that the time element of the device T may be made any desired value, so that the periodic action on the part of the engineer may be required at any desired time intervals.

It should also be pointed out that should the engineer attempt to defeat the purpose of the acknowledging feature by holding the device T in its wound up position, contac" 10 would remain open, and the brakes would be applied as soon as relay R be-. comes de-energized.

As stated hereinbefore, means may be interposed in the main circuit for magnet M whereby this magnet will be de-energized if the train exceeds a given high speed even though relay R is energized. Referring now to F ig. 4.v the main circuit for magnet M is from terminal B. through contact 4 of relay R, wire 5, contact 13 controlled by centrifugal device C, wires 5 and 6, winding of magnet M, and wire 7 to terminal 0. Contact 13 is normally closed, but opens when the train is above a given high speed limit. In all other respects the apparatus illustrated in Fig. 4 is the same as that shown in Fig. 1.

In the modification shown in Fig. 3, the control of relay R by the trackway current, and the control of magnet M by contact 4 of relay R, are the same as in Fig. 1. Contact 13 is controlled in accordance with the speed of the train as in Fig. 1. The mechanical slow releasing device T is, however, replaced by pneumatic apparatus which I will now describe.

The reference character Q designates a valve which is controlled by a magnet WV.

Valve Q comprises a valve body 48 containing a chamber 47 provided with a valve member 46 biased to its'closed position by a spring 49. Chamber 4? is constantly supplied with fluid under pressure, usually air, from a source not shown in the drawing, through a port 50. hen magnet W is energized, valve member 46 is moved downwardly against the bias of spring 49 and air is then supplied, by pipe 51, to the under side of a piston 55 in a cylinder54. This air drive piston 55 upwardly against the bias exerted by a spring 56. If now, valve Q, be closed, the air is trapped in cylinder 54 and holds piston 55 in its upper position. This air under pressure is, however, slowly dissipated to atmosphere through a restricted port 52 in valveQ. After a time interval the pressure under piston 55 is so reduced that spring 56 returns piston 55 to its lower position. Two contacts 43 and 41 are so controlled by piston 55 that when the piston is in its lower position cont-act 43 is closed and contact 41 is open, but that when the piston is in its upper position contact 41 is -closed and contact 43 is open.

lVhen relay R is energized, magnet M is energized over front contact 4 as in Fig. 1. When this relay becomes de-energized the brakes will be applied unless the engineer takes suitable action. A normally open manually operable circuit controller 42 is provided on the train. When the engineer closes circuit controller 42, a circuit is closed from terminal 13, through back contact 8 of relay R, wire 9, contact 43, wire 44, magnet l/V, wire 45, and circuit controller 42 to terminal 0. Magnet W is therefore energized and valve Q, is opened, thereby causing piston 55 to rise. Contact 43 is then opened, interrupting the circuit for magnet l/V. Contact 41, is however closed, and remains closed for an interval of time. If the speed of the train is not above miles per hour, current then flows from terminal B, through back contact 8 of relay R, wire 9, contact 41, wire 12, contact 13, wires 14 and 6', magnet M, and wire 7 to terminal O, and the brakes are not applied. At the expiration of a time interval piston returns to its'lower position and opens contact 43, but contact 41 is then closed and the engineer may operate circuit controller 42 as before to prevent a brake application.

Should the engineer hold circuit controller 42 closed, it can not prevent improper operation of the apparatus for as soon as valve Q is opened contact 43 opens to break the circuit for magnet W.

Although I have herein shown and described only two forms of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

I safe,

Having thus described my invention, what I claim is:

'1. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, and means located entirely on the train for preventing an automatic brake application if the engineer takes suitable periodic action.

2. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, and means located entirely on the train for preventing an automatic brake application if the engineer takes suitable action at fixed intervals of time.

3. Railway traffic controlling; apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, and means located entirely on the train for preventing an automatic brake application if the speed does not exceed a given value and the engineer takes suitable periodic action.

4. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, and means located entirely on the train for preventing an automatic brake application if the speed does not exceed a given value and the engineer takes suitable action at fixed time intervals.

5. In combination, a train carried relay controlled from the trackway and arranged to be energized or de-energized according as traffic conditions in advance are safe or unsafe, a brake controlling magnet controlled by said relay and energized when said relay is energized, a slow acting device on the train including a normally open contact, and requiring periodic manual operation to keep said contact closed, and a circuit for said magnet controlled by said contact and by a back contact of said relay.

6. In combination, a train carried relay controlled from the trackway and arranged to be energized or deenergized according as traffic conditions in advance are safe or una brake controlling magnet governed by said relay and normally (lo-energized when the relay is tie-energized, a slow acting device on the train including a normally open contact and requiring periodic manual operation to keep said contact closed, and means operating when said relay is de-energized to keep said magnet energized while said contact is closed if the speed of the train does not exceed a given value.

7. In combination, a train carried relay controlled from the trackway and arranged to be energized or de-energized according as traffic conditions in advance are safe or unsafe, a brake controlling magnet governed by said relay and normally de-energized when the relay is de-energized, and means located on the train for keeping saidmagnet energized while said relay is de-energized rovided the speed does not exceed'a given value and the engineer takes suitable periodic action.

8. Railway traffic controlling apparatus comprising means for supplying train governing current to the track rails under safe traffic conditions in advance and for discontinuing the supply of such current under unsafe traffic conditions in advance, automatic train carried mechanism controlled by said train governing current for applying the brakes in the absence of said current, and means located entirely on the train for preventing oporation of said automatic mechanism in the absence of said train governing current provided that the engineer takes suitable periodic action.

9. Railway traffic controllling apparatus comprising means for supplying train governing current to the track rails under safe traffic conditions in advance and for discon- -tinuing the supply of such currentunder unsafe traffic conditions in advance, automatic train carried mechanism controlled by said train governing current for applying the brakes in the absence of said current, and means located entirely on the train for preventing operation of said automatic mechanism in the absence of said train governing current provided that the engineer takes suitable periodic action and the speed of the train does not exceed a given value.

10. In combination, a spindle biased to one position and arranged when moved out of such position to return thereto with a uniform slow angular velocity, a first contact arranged to be closed when said spindle is moved away from such one position, a knob biased to a given position and capable of manual movement away from such position to move said spindle away from said one position, and a second contact closed only when said knob occupies said given position.

11. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, a spindle biased to one position and arranged when moved out of such position to return thereto with a uniform slow angular velocity, a first contact arranged to be closed when said spindle is moved away from such one position, a knob biased to a given position and capable of manual movement away from such position to move said spindle away from said one position, a second contact closed only when said knob occupies said given position, and means controlled by said first and said second contacts for preventing an automatic brake application.

12. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, a spindle biased to one position and arran ed when moved out of such position to return thereto with a uniform slow angular velocity, a first contact arranged to be closed when said spindle is moved away from such one position, a knob biased to a given position and capable of manual movement away from such position to move said spindle away from said one position, a second contact closed only when said knob occupies said given position, and means efiective only when said two contacts are closed to prevent an automatic brake application.

13. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traflic conditions to apply the brakes, a fluid pressure device on the train, manually operable means controlled by said device for actuating the device, and means controlled by said device for preventing an automatic brake application.

14. An automatic train control system comprising means for controlling the vehicle brakes in accordance speed under favorable traliic conditions ahead, means for applying the vehicle brakes and bringing the vehicle substantially to a stop under unfavorable traflic conditions and means for preventing said last mentioned brake application bringing the train to a stop if a manually operable device is operated at predetermined intervals under unfavorable traflic conditions.

15. Railway traffic controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traflic conditions to apply the brakes, a slow acting device on the train including a contact and responsive to periodic manual operation to keep the contact closed, and means controlled by said device for preventing an automatic brake application.

16. Railway traflic' controlling apparatus comprising automatic mechanism carried on a train and operating under unsafe traffic conditions to apply the brakes, a slow acting device on the train includinga contact and responsive to periodic manual operation to keep the contact closed, and means controlled by said device and by the speed of the train for preventing a brake application by said automatic mechanism.

17. In an automatic train control system, the combination of a brake setting appliance, means controlling said'brake setting appliance in accordance with the vehicle speed, means responsive to vigilance on the part of the engineer upon the approach of his train to a signal at danger and thereafter at repeated intervals by actuating a manually operable device, and means for actuating said brake setting appliance to effect a brake apwith the vehicle of speed if the engineer plication regardless manually operable device fails to actuate said when required.

18. An automatic train control system comprising a normally energized device which if de-energized eflects' an automatic brake application, two independent means for maintaining said device energized, one of which is effective so long as the train is traveling in clear territory, and the other of which is effective if a suitable manually operable device is operated at repeated intervals, and means for effecting an automatic brake application in clear territory if a predetermined maximum speed limit is exceeded.

19. In an automatic train control system, the combination of a brake setting appliance, means responsive to manifestation of vigilance on the part of the engineer upon the approach of his train to a signal at danger and thereafter at repeated intervals by actuating a clock-work time release device, and means for actuating said brake setting appliance to effect a brake application regardless of speed if the engineer fails to actuate said time release device when required.

In testimony whereof I affix my signature.

RONALD A. MGCANN. 

